First acceleration of heavy ion beams with a superconducting continuous wave (cw) -Linac RF-structure at GSI
After successful RF-testing of a new superconducting Linac RF-cavity in 2016 and a short commissioning and ramp up time of some days, this Crossbar H-cavity, designed at Institute of Applied Physics of Goethe University Frankfurt, accelerated first time heavy ion beams with full transmission up to the design beam energy. For the first beam test the superconducting cavity was powered with 10 Watt of net RF power providing for an accelerating voltage of more than 1.6 Mega Volt inside a length of less than 70 cm. Meanwhile the design acceleration gain (3.5 Mega Volt) has been verified with heavy ion beam of up to 1.5 particle micro Ampere. The measured beam parameter, delivered by an Electron Cyclotron Resonance ion source and the GSI High Charge State Injector, show a nice beam quality – further and more detailed tests and careful evaluation of data are envisaged. Successful beam testing could not be accomplished without strong support of highly committed people from different GSI-departments (Linac-RF, Beam diagnostics, Ion sources, Transport&Installations, Accelerator Operations and many others). The beam test is a milestone of the R&D work of Helmholtz Institute Mainz and GSI in collaboration with Goethe University Frankfurt in preparation of a superconducting heavy ion continuous wave linear accelerator.
Winfried Barth, Florian Dziuba and Maksym Miski-Oglu for the cw-Linac team of HIM and GSI